sctp: fix to check the source address of COOKIE-ECHO chunk

SCTP does not check whether the source address of COOKIE-ECHO
chunk is the original address of INIT chunk or part of the any
address parameters saved in COOKIE in CLOSED state. So even if
the COOKIE-ECHO chunk is from any address but with correct COOKIE,
the COOKIE-ECHO chunk still be accepted. If the COOKIE is not from
a valid address, the assoc should not be established.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 27 insertions, 16 deletions

diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index f87ccb11a520..a7b65e9e44b3 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -2242,14 +2242,17 @@ int sctp_verify_init(const struct sctp_association *asoc,
  * Returns 0 on failure, else success.
  * FIXME:  This is an association method.
  */
-int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
+int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
                       const union sctp_addr *peer_addr,
                       sctp_init_chunk_t *peer_init, gfp_t gfp)
 {
         union sctp_params param;
         struct sctp_transport *transport;
         struct list_head *pos, *temp;
+        struct sctp_af *af;
+        union sctp_addr addr;
         char *cookie;
+        int src_match = 0;
 
         /* We must include the address that the INIT packet came from.
          * This is the only address that matters for an INIT packet.
@@ -2261,18 +2264,31 @@ int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
          * added as the primary transport.  The source address seems to
          * be a a better choice than any of the embedded addresses.
          */
-        if (peer_addr) {
-                if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
-                        goto nomem;
-        }
+        if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
+                goto nomem;
+
+        if (sctp_cmp_addr_exact(sctp_source(chunk), peer_addr))
+                src_match = 1;
 
         /* Process the initialization parameters.  */
         sctp_walk_params(param, peer_init, init_hdr.params) {
+                if (!src_match && (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
+                    param.p->type == SCTP_PARAM_IPV6_ADDRESS)) {
+                        af = sctp_get_af_specific(param_type2af(param.p->type));
+                        af->from_addr_param(&addr, param.addr,
+                                            chunk->sctp_hdr->source, 0);
+                        if (sctp_cmp_addr_exact(sctp_source(chunk), &addr))
+                                src_match = 1;
+                }
 
                 if (!sctp_process_param(asoc, param, peer_addr, gfp))
                         goto clean_up;
         }
 
+        /* source address of chunk may not match any valid address */
+        if (!src_match)
+                goto clean_up;
+
         /* AUTH: After processing the parameters, make sure that we
          * have all the required info to potentially do authentications.
          */
diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index 3b80fe24dabf..d612ca1ca6c0 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -595,8 +595,7 @@ static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
          * fail during INIT processing (due to malloc problems),
          * just return the error and stop processing the stack.
          */
-        if (!sctp_process_init(asoc, chunk->chunk_hdr->type,
-                               sctp_source(chunk), peer_init, gfp))
+        if (!sctp_process_init(asoc, chunk, sctp_source(chunk), peer_init, gfp))
                 error = -ENOMEM;
         else
                 error = 0;
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index ad3b43bb75cc..ab949320468d 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -393,8 +393,7 @@ sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep,
                 goto nomem_init;
 
         /* The call, sctp_process_init(), can fail on memory allocation.  */
-        if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type,
-                               sctp_source(chunk),
+        if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk),
                                (sctp_init_chunk_t *)chunk->chunk_hdr,
                                GFP_ATOMIC))
                 goto nomem_init;
@@ -725,7 +724,7 @@ sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep,
          */
         peer_init = &chunk->subh.cookie_hdr->c.peer_init[0];
 
-        if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type,
+        if (!sctp_process_init(new_asoc, chunk,
                                &chunk->subh.cookie_hdr->c.peer_addr,
                                peer_init, GFP_ATOMIC))
                 goto nomem_init;
@@ -1464,8 +1463,7 @@ static sctp_disposition_t sctp_sf_do_unexpected_init(
          * Verification Tag and Peers Verification tag into a reserved
          * place (local tie-tag and per tie-tag) within the state cookie.
          */
-        if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type,
-                               sctp_source(chunk),
+        if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk),
                                (sctp_init_chunk_t *)chunk->chunk_hdr,
                                GFP_ATOMIC))
                 goto nomem;
@@ -1694,8 +1692,7 @@ static sctp_disposition_t sctp_sf_do_dupcook_a(const struct sctp_endpoint *ep,
          */
         peer_init = &chunk->subh.cookie_hdr->c.peer_init[0];
 
-        if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type,
-                               sctp_source(chunk), peer_init,
+        if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), peer_init,
                                GFP_ATOMIC))
                 goto nomem;
 
@@ -1780,8 +1777,7 @@ static sctp_disposition_t sctp_sf_do_dupcook_b(const struct sctp_endpoint *ep,
          * side effects--it is safe to run them here.
          */
         peer_init = &chunk->subh.cookie_hdr->c.peer_init[0];
-        if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type,
-                               sctp_source(chunk), peer_init,
+        if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), peer_init,
                                GFP_ATOMIC))
                 goto nomem;